Apparatus for grounding electrostatic charges



y 1961 I w. SPENGLER 2,983,847

APPARATUS FOR GROUNDING ELECTROSTATIC CHARGES Filed June 9, 1959 7 i//i P 4 INVENTOR WALTER SPE/VGLE R United States Patent APPARATUS FOR GROUNDING ELECTROSTATIC CHARGES Walter Spengler, Lange Gasse 2'4, Basel, Switzerland Filed June 9, 1959, Ser. No. 819,087

Claims priority, application Switzerland June 11, 1958 3 Claims. (Cl. 315-111) My invention has for its object an arrangement for diverting electrostatic charges from the outer surfaces of material having a poor conductivity through the agency of glow discharges.

According to my invention, there is provided a barshaped member of a rectangular cross-sectional outline, made of insulating material and carrying on at least one of its lateral surfaces a series of parallellongitudinally extending wires forming the electrodes while there are formed in said member between said wires and in parallelism therewith, recesses inside which recesses are fitted rule-shaped counter-electrodes carrying electrode points projecting freely outwardly but stopping short of the outer edges of said recesses, this arrangement providing for the formation of a corona discharge field between said electrode points and the two adjacent wires, said field extending during operation throughout the lateral surface of the bar-shaped member. It is thus possible to obtain over said surface a field distributed over a comparatively large area, the efiiciency of the arrangement reaching a maximum value in a predetermined direction. This is of a particular advantage when it is desired to remove the static charges carried for instance by paper or textile strips.

I have illustrated by way of example in the accompanying drawings two prefered embodiments of my invention. In said drawings:

Fig. l is a perspective view of a portion of an arrangement according to the first embodiment.

Fig. 2 shows in a similar manner a section of an arrangement according to a second embodiment.

The arrangement according to Fig. 1 includes a rodshaped member a made of insulating material such as hard or so-called bakelized paper material. The upper surface of said member is provided with longitudinally extending, electrode-forming wires b secured in any suitable manner to the said member a. These wires are connected at one end of said rod-shaped member with a common grounding cable which is not illustrated. Between any two successive wires there is provided in the member a a groove-shaped recess c extending in parallel with the wires and in which are fitted rule-shaped electric leads d forming counter-electrodes. These leads d carry each a plurality of electrode points d1 projecting outwardly of the leads without extending beyond the corresponding recess 0, the different leads being also connected in registry with the one of the rod-shaped members a with a common cable which is not illustrated.

For operation of the arrangement, the cable feeding ice the leads ,d is connected with a high voltage supply of alternating current while the cable connected with the wires b is grounded. This leads, as well known in the art, to the production of corona fields by the glow dischanges between the electrode points d1 and the wires b which fields serve for carrying away the undesired electrostatic charges, for instance those carried by paper or textile strips or again by strips of synthetic material.

In the embodiment illustrated in Fig. 2, there are provided on both opposite lateral sides of the insulating member m wires n while the recesses 0, between the locations of said wires appear in the shape of slots. The leads p extending inside said slots carry fins r, extending through and beyond the corresponding leads and showing electrode points r1 facing opposite directions without projecting any more then precedingly beyond the corresponding flat surfaces of the insulating member m.

The advantages of the arrangement disclosed have been already given hereabove so that it is not necessary to enter into any further detail.

What I claim is:

1. An apparatus for grounding electrostatic charges from the surfaces of materials having poor conductivity, said apparatus comprising a member'of insulating material having at least one flat surface with a plurality of parallel grooves therein, wires on said flat surface between said grooves and parallel thereto, said wires being grounded, an electrode in each groove having a plurality of points thereon extending outwardly to a level just below said fiat surface, and a source of high AC. voltage to one side of which said electrodes are coupled.

2. An apparatus for grounding electrostatic charges from the surfaces of materials having poor conductivity, said apparatus comprising a member of insulating material having a flat surface with a plurality of parallel grooves therein, wires on said flat surface between said grooves and parallel thereto, a common ground lead to which said wires are connected, an electrode in each groove having a plurality of points thereon extending outwardly to a level just below said flat surface, a common power lead to which said electrodes are connected, and a source of high AC. voltage to one side of which said common power lead is coupled.

3. An apparatus for grounding electrostatic charges from the surfaces of materials having poor conductivity, said apparatus comprising a member of insulating material having two flat surfaces each having a plurality of parallel grooves therein, wires on each flat surface between said grooves and parallel thereto, a common ground lead to which said wires are connected, an electrode in each groove having a plurality of points thereon extending outwardly to a level just below the level of said fiat surfaces, 21 common power lead to which said electrodes are connected, and a source of high AC. voltage to one side of which said common power lead is coupled.

References Cited in the file of this patent UNITED STATES PATENTS 871,652 Ward Nov. 19, 1907 1,218,817 Tennant Mar. 13, 1917 2,768,310 Kazan Oct. 23, 1956 2,881,346 Johnson Apr. 7, 1959 

